Access to an abundance and variety of foods is part of a healthy diet. Consumers in many countries have gained access to new crop commodities from globalization and international trade. Yet, the diversification of their diets may come at the cost of global crop diversity and the fate of food security.

These were among the conclusions of a recent study published in the Proceedings of the National Academy of Sciences. Researchers sifted through a large database to track per capita food supply changes in 152 countries over five decades. They found that some food staples such as wheat, rice, and maize grew more abundant in people’s diets across the world. Abundance of oil crops such as soybean and palm, increased, while abundance of regionally important staples such as millet, sorghum, and cassava decreased. The average diversity of food commodities increased at the national level, giving consumers in some countries more choices at the market. However, those newly available crop commodities were often the same as ones already available in other countries, leading to a net change towards global crop homogeneity. The study’s authors estimated that 94 crop species provide 90 percent of the global supply of calories, protein, and fat.

The higher food diversity in national markets suggests millions more can enjoy the gastronomic advantages of a westernized diet, even if it is heavy on fats and sugar. The ubiquity of the same crops, however, means countries will increasingly be competing for the same food supply. As a result, the food security and economies of more countries may be vulnerable to catastrophic events such as Typhoon Haiyan that disrupted coconut oil exports from the world’s leading supplier, the Philippines. As dominant crops replace regional varieties, net global plant genetic diversity decreases. A genetic diversity shortage will make it more difficult for plants to adapt to a changing climate and farmers to adapt to shifts in dietary preferences.– Miles Becker| 17 March 2014

Source: Khoury et al. 2014. Increasing homogeneity in global food supplies and the implications for food security. Proceedings of the National Academy of Sciences doi: 10.1073/pnas.1313490111